1. Field of the Invention
This invention relates to a method for producing a magnetic head which is carried on a magnetic disc apparatus, a magnetic tape apparatus, etc. and which can realize a magnetic recording of high density. More particularly, it relates to a method for producing a magnetic head wherein the track portion and/or slider portion of a core made of ferrite, an Fe-Al-Si alloy or the like is worked precisely with low deformation. More specifically, it relates to a method for working the track portion and/or slider portion of a magnetic head core.
2. Brief Description of the Prior Art:
In recent years, as the density of recording has become higher, the track portion of a magnetic head has tended to become increasingly narrower.
Heretofore, the track portion of a ferrite magnetic head has been principally worked by grinding or mechanical polishing. However, by way of example, in the case where a track portion having a width of 20 .mu.m or less is worked by this method, chipping attributed to the brittleness of the ferrite or the influence of a worked layer or deformed layer is not insignificant, and inevitably the available percentage of production or the performance of the magnetic head lowers sharply. Especially, it is a problem that the reproduced output characteristics of such devices and the crosstalk characteristics are unsatisfactory.
As alternative methods, there have been proposed ion etching and electrolytic etching, each of which employs a mask having a pattern corresponding to a configuration to be worked. These processes, however, have the fatal disadvantage in practice that the erosion rate is low, so that such methods have not been put into practical use as yet. With, for example, the ion etching process, even when the etching is performed for 1 hour, the amount of ferrite removed is only about 1 .mu.m. Accordingly, a working time of at least 50 hours is necessary for ion etching of 50 .mu.m or more as required ordinarily. It is next to impossible to spend such a long time in production, from a point of view of economy of manufacture.
As an improvement on the aforecited method, there has also been proposed a method wherein a core made of ferrite is ion-etched with its track portion covered with a mask, to remove the other area than the masked portion to a depth of approximately 5 .mu.m, whereupon as an auxiliary working, the gap portion other than the track portion is cut with a laser beam or the like so as to adjust the track width. However, this method also has the problem that an increase in the production cost is incurred on account of the complicated manufacturing process, so it also has not been put into practical use as yet.
As known arts akin to this invention, the following can be mentioned:
(i) Japanese Patent Application Publication Specification No. 39-18284, and
(ii) Japanese Patent Application Laid-open Specification No. 51-114111.